Ms. MacKinnon, 50, is a theater industry leader who is president of her profession’s union, the Stage Directors and Choreographers Society, and serves as a tireless champion of Clubbed Thumb, a small company in downtown New York where she is chairwoman of the board. She intends to continue leading the union; she will switch to the Clubbed Thumb advisory board, and hopes to bring some of its productions to San Francisco.

Born in Chicago to Canadian parents, Ms. MacKinnon was raised in Toronto and Buffalo; she currently lives in New York, and will relocate to the Bay Area. She previously lived in Southern California for four years, as a graduate student at the University of California, San Diego.

Ms. MacKinnon has directed seven Broadway shows in the last six years — a rare feat for a woman in a commercial theater landscape dominated by male directors. Her shows include “The Parisian Woman,” a currently running play starring Uma Thurman, as well as last season’s musical “Amélie,” starring Phillipa Soo, and the previous season’s “China Doll,” starring Al Pacino. (“Amélie” began its life in the Bay Area — Ms. MacKinnon directed a pre-Broadway production in 2015 at Berkeley Repertory Theater. She also directed a 2005 production of “3F 4F,” by Victor Lodato, at San Francisco’s Magic Theater, and she has led workshops at A.C.T.)

She won a Tony Award in 2013 for her direction of a revival of “Who’s Afraid of Virginia Woolf?” and was nominated in 2012 for “Clybourne Park.” She is known as an interpreter of Edward Albee, the playwright who wrote “Virginia Woolf.”

“I’ve always been a freelance director, but now I feel ready to build something bigger than myself — to put myself into an institution, producing a body of work and trying to learn as well as grow from a particular audience,” Ms. MacKinnon said in a telephone interview from San Francisco, where the appointment was announced. “And San Francisco is a great city.”

She said that among her priorities will be producing more new plays by young writers.

Ms. MacKinnon said she would continue to direct, both at A.C.T. and in New York. This spring she is scheduled to direct “Log Cabin,” a new play by Jordan Harrison at Playwrights Horizons, an Off Broadway nonprofit, and she said she will “absolutely continue to direct on Broadway — I’m so excited to continue that strand of my career, and A.C.T. is excited that I’m in it.”

A.C.T., founded in Pittsburgh in 1965 and relocated to San Francisco in 1967, is a prominent regional theater, with 11,000 subscribers, 100 staff members and an annual operating budget of $23 million. The theater, which won a special Tony Award for regional theater in 1979, produces seven shows each subscription season, as well as a Christmas show and off-subscription events; the theater also oversees a conservatory.

Ms. MacKinnon’s appointment comes amid what is shaping up to be a wave of leadership changes at American regional theaters. A significant number of artistic directors around the country are leaving their longtime positions, including in the Bay Area not only Ms. Perloff but also Tony Taccone, the artistic director of Berkeley Rep.